1. Field of the Invention
The invention relates to an internal combustion engine, having a hydraulic system which includes a hydraulic pump, and having a lubricant system, for moving parts of the engine, which includes a lubricant pump.
2. Description of the Prior Art
One engine of the type with which this invention is concerned is known on the market. For its moving parts, such as pistons, crankshaft, and so forth, a forced-circulation lubrication is provided, which is supplied from an oil sump via an oil pump. At the same time, in the known engine, a hydraulic system is provided which is used to actuate the inlet and outlet valves of the engine. The known engine accordingly has no camshaft. Such an engine has the advantage that the control times for the inlet and outlet valves are independent of the position of the piston of the applicable cylinder. Depending on the operating state of the engine, such as high rpm, and on the torque desired by the driver, valve opening and closing times can be achieved that enable operation of the engine especially optimally in terms of emissions and fuel consumption.
The hydraulic system of the known internal combustion engine is supplied from a hydraulic reservoir via a high-pressure hydraulic pump. A hydraulic cylinder supplied from the hydraulic system is connected to the tappet of a gas exchange valve, such as an inlet or outlet valve, and leads to an opening or closing motion of this valve.
The object of the present invention is to refine an internal combustion engine of the type defined at the outset in such a way that it is as small as possible in structure and can be produced as inexpensively as possible.
In an internal combustion engine of the type defined at the outset, this object is attained in that the hydraulic pump is connected to the lubricant system in such a way that it is lubricated by the lubricant of the lubricant system.